DE2933801A1 - BELT DISC FOR BELT ADJUSTMENT GEARBOX - Google Patents

Description

PATENT LAWYERS

DR.-ING. H. FINCKE DIPL.-ING. H. BOHR DIPL.-ING. S. STAEGER

Patent attorneys Dr. Find · · Bohr. Staeoer ■ Garbage mtr. 31 8000 Munich

eOOO MUNICH 9, MCIIeritraBe 31 Telephone: (089) 26ί0ο0 Telegrams: Claims Munich Telex: 523903 claim d

Mop "No. B310 Specify BiHe in the answer

August 21, 1979

SOCIETE ANONYME FRANCAISE DU FERODO 64 Avenue de la Grande-Army

75017 Paris / FRANCE

Belt pulley for belt adjustment gear

PRIORITY: August 21, 1978 - No. 78 24276 - FRANCE

030010/0811

• end connection. loyer. Vereinibonk MOnchtn, account "" 404 (IU 700MJ 70) · Poihdwckkonto: MOnchen 27044-802 (BU 700100M)

(only »Α Dipl.-Ing. S. Stowger)

¹ pulley for belt adjustment gear '

The present invention relates generally to belt type variable displacement transmissions of the kind that are able to drive any unit in a controlled manner from a To be used engine ago, for example in a motor vehicle, to an auxiliary unit from the engine to drive, in particular an AC or three-phase alternator, a water pump or a fan, which are normally provided as equipment for such a vehicle.

As is known per se, such a variable speed drive generally comprises two pulleys, one of which drives and the other is driven, and one looped over these pulleys in an endless loop Belt, with the pulleys facing each other two coaxial flanges with frustoconical side surfaces have, one of which is called a movable flange and slidably mounted on a rotatable shaft is, wherein it is tightened or wedged on this for rotation, and of which the other, the fixed flange is called, is not only pulled up or tapered to rotate on this shaft, but at least functionally

030010/081 1

--6-

is also axially attached to this, in cooperation with elastic restoring devices which preload the movable flange in the direction of the fixed flange.

The present invention is directed more precisely to those adjusting gears in which the elastic return devices, which have one as well as the other of their pulleys, of an annular part or a membrane or a disc spring are formed, which on the one hand has a peripheral portion which is a disc spring forms which is in axial contact with the movable flange of such a pulley, and on the other hand a central section, which is divided into radial fingers by slits and against a bearing part is applied, which is rotatably mounted or wedged on the shaft of the pulley and axially on this is fixed.

In practice, rotary connection lugs are provided between the contact part and the woodruff key.

In the previously known embodiments of this type these rotary connection lugs carried by the plant part or support part and either engage in the slots, which separate two of the fingers of the woodruff key, or in channels or openings that for this purpose in the mentioned fingers are introduced.

In one case as in the other, they are supported in the circumferential direction on the narrow surfaces of the woodruff spring that are parallel to the axis of the assembly.

In addition, in the embodiments of this type, which are known to this day, the circumference along which the disc spring is axially supported on the support part is the same again, along which the rotary connection lugs also act,

030010/0811

which is provided between this woodruff key and this support part are.

Finally, in the embodiments of the subject Type that are known to this day, the bearing surface of the support part, along which the disc spring is axially on this supports, an annular support surface that is common to all radial fingers of this woodruff.

Although such embodiments have so far been satisfactory were and are also still satisfactory, they have various disadvantages, which are mentioned below will.

Since first the axial support of the woodruff key takes place on the support part in the vicinity of the rotary connection lugs, which are provided between this woodruff key and this support part, lead the openings for the fingers of the woodruff spring, in which these lugs engage, inevitable to a reduction in the surface along which the Woodruff spring is effectively supported against the bracing.

If you now take into account the relatively high axial load caused by the contact between the woodruff key and the support surface is produced, this entails that the axial surface of this disc spring to support this support part should be as large as possible in order to reduce wear in this area reduce to a minimum.

In addition, the fingers of the woodruff key are arched, and because they rest against a circular ring-shaped joint Support surface of the support part are located, it follows that for each of these fingers the corresponding Support surface is limited and that it is corresponding to the inclination or inclination of such a radial

030010/0811

Fingers in use with respect to the axis of such a circular support surface changes.

In addition, in the known arrangements in which the lugs of the support part engage in slots, the respective Separate two fingers of the woodruff key, the width of these slots in the course of the function or the Subject to change in operation, which affects the centering of the woodruff key.

The present invention has the general object of completely or partially suppressing these disadvantages.

More precisely, the present invention aims at a pulley for a variable speed drive, which is of the type having opposite one another two coaxial flanges with frustoconical side surfaces, of which the a movable flange is called and is slidably mounted on a rotatable shaft while engaging with it for common rotation, and the other of which is called the fixed flange and not just for rotation is firmly connected to the shaft, but also at least functionally axially firmly connected to this, in cooperation with an elastic return device, which the movable flange in the direction of said fixed Flange pretensioned, the elastic restoring device from an annular part or a disc spring formed which on the one hand has a peripheral part that forms a plate spring and is in contact against the movable flange is located, and on the other hand has a central part, which through slots in radial Finger is separated and is in contact with a support part that rotates with the corresponding shaft is connected and is axially fixed on this, with rotary connection lugs between the support part and the disk benfeder are provided, which either of the support part or woodruff springs and which are in circumferential

030010/0811

4t

direction on small surfaces belonging to the other of these named parts, parallel to the axis of the assembly, this pulley being characterized in that the lugs are carried by the disc spring, the small curses with which they interact are firmly or integrally connected to the support part.

According to a possible embodiment of the invention, the support part has receptacles such as, for example, slots, Recesses or troughs, each of which engages a nose firmly connected to the woodruff key, and wherein the lateral flanges or side surfaces which such a receptacle on its circumferential direction Has ends which form small surfaces with which such a nose cooperates in the rotary connection.

For example, these receptacles of the support part can be formed on a generally axial section thereof, and the lugs of the disc spring may extend generally in a radial direction, the lugs for example are formed directly by the radial fingers of this woodruff key or by parts that are with these are connected.

The contact of such a radial finger of the woodruff key on the support part takes place without interruption.

In other words, the bearing surface of the woodruff key the support part is as large as possible, and the wear in this area is advantageously to a minimum reduced.

According to another possible embodiment of the invention, the receptacles are the support part for the noses which forms the disc spring, from a generally radial part

030010/0811

of said support member formed, and the lugs extend generally in the axial direction, said lugs for example directly by angled or right-angled bends of the radial fingers of the woodruff key or are also formed by parts that are connected to them.

Be that as it may, the support of a finger of the woodruff key on the support part takes place in an advantageous manner without Interruption as before,

the circumference along which such support occurs differs from the circumference along which the rotary connection lugs, which are provided between the disc spring and the support part, are effective.

In addition, according to the invention, the bearing surface of the support part is on which a radial finger of the woodruff spring is supported axially directly or indirectly, preferably part of a cylinder made up of generatrices perpendicular to the central radial plane of said finger.

In addition, such a radial finger is advantageously flat or flat at least in the area in which it is intended for contact with the cylindrical portion of the support part.

This means that, in use, the effective support surface of such a finger is opposite the woodruff spring the support surface does not change in the course of the function, as does the inclination of this finger of the woodruff key may be opposite the axis of the contact surface of the support surface with which it is in contact.

Finally, according to the invention, the small surfaces or facets with which the noses interact are preferred to a radial median plane of the corresponding) finger

030010/0811

parallel, which allows excellent centering of the woodruff key during operation.

In any case, the word "facet" or "small area" must be used here. to be understood in a broad sense, with such a surface in reality on two coplanar support lines can be reduced.

The aims or objects of the invention, its features and its advantages emerge from the rest of the following Description, which is carried out, for example, with reference to the accompanying schematic drawings, in which:

Fig. 1 is a view of an axial section of a pulley for a variable speed transmission according to FIG Invention is

2 shows a partial view in axial section of a single disk spring, on different scales which comprises such a pulley, as well as the support part, which this is associated where it is assumed that this woodruff key is in a position in which it is essentially perpendicular to the axis of the assembly,

FIG. 3 shows a partial view of this woodruff key and this support part along the arrow III in FIG. 2 is,

Fig. 4 is a partial view in section along line IV-IV in Fig. 2;

Fug. «5 and 6

Views analogous to those of FIGS. 2 and 3 and relate to an embodiment variant,

Figures 7 and 8

in the same way views are analogous to those of FIGS. 2 and 3 and relate to a different embodiment variant,

030010/0811

FIG. 9 is a view analogous to that in FIG. 2 and a

relates to yet another embodiment variant, FIG. 10 is a longitudinal partial sectional view of this variant

Line X-X in fig. 9, fig. 11 is a view analogous to that of fig

and relates to an embodiment variant, FIG. 12 is a view analogous to that of FIG. 10

and concerns another embodiment variant, and
FIG. 13 is a view partially showing that of FIG

Fig. 3 resumes and focuses on a

Design variant refers.

As is known, an adjusting gear has two pulleys on which a drive belt is in an endless loop is performed, namely a driving pulley and a driven pulley.

In Fig. 1, a single one of these pulleys is shown and it is, for example, the driven pulley 10; likewise, only a section of the associated drive belt is shown under the reference number 11.

The pulley 10 has opposite two coaxial flanges with a frustoconical flank, from which one, which is denoted by the reference numeral 12 and hereinafter referred to as the movable flange, under the Control of elastic restoring devices mounted axially movable relative to the other flange that eats the Bears reference numeral 13 and is referred to below as a fixed flange.

In the illustrated embodiment, the movable flange 12 is with its inner circumference on a tubular Hub 14 carried by which it is slidably mounted on a shaft 15.

030010/0811

In the illustrated embodiment, this shaft is in two parts: an axial part, which in turn consists of two shafts lenstumpfen is formed, namely with a stub shaft larger diameter 15A and a stub shaft with a smaller diameter 15B, and a circumferential section 15C, the forms a sleeve in which the fixed flange 13 is carried at one of its ends.

This bushing 15C which engages with the smaller diameter stub shaft 15B of the axial portion of the axle 15 is and is connected to it in a rotationally fixed manner by a feather key 16, rests axially against the end of a hub 17, which in turn towards the end of the stub shaft with larger diameter 15A of said axial portion of the shaft 15 is applied and carries one or more pulleys 16 to drive any units, for example one Three-phase alternator.

A screw 19 holds the bush 15C in contact with the hub 17 with the action of a washer 20.

Thus, the fixed flange 13 is not only pulled up for rotation on the shaft 15, but it is also axial therewith tied together.

The elastic return device that moves the movable flange 12 in the direction of the fixed flange 13 bias towards, is formed by an annular part 21, which is called the disc spring and on the one hand a has circumferential section 22 which forms a plate spring which rests axially against the movable flange 12, and more precisely against a bent edge 23, which this has on its outer circumference, as well as on the other hand a central part, which is divided into radial fingers 24 and axially rests against a support part 26, which on the sleeve 15C is carried at that end of it,

030010/0811

- A 4 "-

which is opposite to that which carries the fixed flange 13.

This support part 26 is now non-rotatably connected to the shaft 25 and axially attached to it.

In the illustrated embodiment, the support part 26 has the general shape of a crucible; it shows you generally radial portion 28 which forms the bottom of this crucible and with which the part is fixed to the sleeve 15C, and a general axial part 29 forming the cylindrical wall of said crucible and the fingers 24 of the woodruff spring 21 rest on the end thereof.

The rotary drive of the movable flange 12 takes place with the action of the woodruff spring 21 via the support part 26 instead.

For this purpose, the circumferential section of the disk spring 21 which forms the disc spring 22 bears protruding engagement blocks or engagement blocks 30 with which the movable Flange 12 engages through recesses 31, which for this purpose it is at its bent peripheral edge 23 carries, and at the same time rotary connection lugs are provided between the disc spring 21 and the support part 26, which are carried either by the support part 26 or the disc spring and in the circumferential direction on the other of the named parts are supported parallel to the axis of the assembly.

According to the invention, these lugs are carried by the disc spring 21, and the surfaces with which they cooperate, are firmly connected to the support part 26.

In the embodiment illustrated by Figures 1 to 4, the noses in question are formed directly by the outer ends 33 of the radial fingers 24 of the disc spring; they are thus lugs that extend generally radially.

030010/0811

At the same time, the axial section 29 of the support part 26 has receiving devices 34 at its free end, wherein such a nose 33 falls into each of these individually, and of which the development in the circumferential direction is complementary to that of the lugs 33; in the illustrated embodiment if these recordings are notch-like perforations, “but they could just as well be hollows.

The lateral flanks 35, which have such a recess 34 at their peripheral ends, thus form the small surfaces for the nose 33, which engages in such a recess, with which such a nose must interact for the rotary connection between the woodruff spring 21 and the support part 26 . These lateral edges 35 parallel to the radial center plane of the finger 24, which an excellent centering of the disc spring ensures during the operation.

In addition, in this embodiment each lug 33 is supported directly against the bottom of the notch or recess 34 in which it engages, and it is thus also the bottom of the recess 34 of the support part 26 via which the woodruff key 21 is axially supported on it .

According to the invention, the bottom of such recesses is formed in such a way that it individually forms a contact surface 36 for the corresponding nose 33. This is preferably formed by a Eylinderabschnitt the generatrix perpendicular to the radial center plane of the finger 24 of the disc spring 21 are provided, the nose 33 forms the corresponding AUB ere end. The part 26 can be produced by pressing in such a way that it has such support surfaces 36 . In addition , the finger 24 is preferably flat, specifically at least in the area in which it is intended to be in contact with the support surface.

030010/0811

The axial support of such a nose 33 is thus found with respect to the support part 26 along an uninterrupted line the entire width or extent in the circumferential direction of such a nose instead, and it is thus independent the operating inclination of the finger 24 of the disc spring 21, whose nose forms the outer end.

The function of the adjusting pulley, which is formed in this way, is also well known for its part, see above that it need not be discussed in detail here; it is enough to remember that in the course of this function the movable flange 12 is between shifted two axial end positions, of which one in Fig. 1 in solid lines and the other in this Fig. 1 is shown in dashed lines.

According to a variant embodiment illustrated by FIGS. 5 and 6 is shown, the lugs 33 are also, as before, through the ends of the fingers 24 of the disc spring 21 itself formed, but they are angled or bent at right angles, in such a way that the lugs are generally axially extend in the direction of the support part 26.

At the same time are the recordings, which this for such Has lugs formed on a generally radial portion 37 to which this part attaches for this purpose ■ has a free end, and ea is in the Ausaführungabebeispiel slits 38 which are radially introduced into this radial section 37 of the Abatützteila 26.

It is expressly pointed out that, as before, the extent of each of these slots 38 in the circumferential direction device is complementary to that of the noses 33. In addition, the flanks of the slots 38 run parallel to the radial one Middle plane of the fingers 24.

030010/0811

At 2333801

In the illustrated embodiment, the radial Section 37 of the support part 26 on its outer circumference Annular bead 39 which protrudes axially and on which the fingers 24 of the disc spring 21 rest.

This bead 39 has already been designed in such a way before that it forms a contact surface 36 for each finger 24 of the disc spring 21, which is of a cylindrical section is formed whose generatrices run perpendicular to the radial center plane of the corresponding finger 24, which in turn is preferably flat.

As can be seen from this arrangement, in contrast to the previous arrangement, the circumference with the diameter D ₁ , along which the disc spring 21 rests axially on the support part 26, differs from the circumference with the diameter D- along which the Noses 33 are effective, which ensure the rotary connection of this woodruff spring with this support.

In the illustrated embodiment, the diameter D _{1 is} greater than the diameter D_; However, a reverse arrangement can also be used: it is sufficient for this that the lugs 33 do not form the actual end of the fingers 24 of the disc spring 21, but angled or right-angled bends which are conveniently punched into these on this side of their end.

In the embodiment shown in FIGS. 7 and 8, the noses 33 are thus angled or right-angled. Bends formed on the outer ends of the fingers 24 of the disc spring 21 are punched out, but as in the embodiment illustrated by FIGS. 1 to 4, the axial support of these fingers 24 takes place on the support part 26 on the same circumference as that which the noses 33 act, the receptacles 40,

030010/081 1

which this support part 26 has for engagement with said lugs, are formed by notches or recesses on the circumference of the radial section 37 this support part are introduced at right angles to the bead 39, which this part in its central portion of a each contact surface 36 has which has such a bead.

The notches 40 have facets or small surfaces which run parallel to the central radial plane of the finger 24.

The support surface 36 is formed by a cylindrical section, the generatrices of which run perpendicular to the central radial plane of the finger 24. This is advantageously even »

As before, the fingers 24 of the woodruff spring 21 are located directly on the support part 26.

In one variant, however, you can also intervene with the interplay of parts that are connected to them.

Such a possibility is illustrated by FIGS. 9 through 12, in which the usually present presence of thickenings or balancing weights 45 on the disc spring 21 is used to increase the response to the centrifugal force.

For example and as shown, each of these thickenings 45 can be carried by a plate or sheet metal 46 with which it is connected to the corresponding finger 24 of the disc spring 21 and which is the surface of this rinfer · »indesten · near its · end doubled.

On this plate 46 there are two shoulders 47 on both sides central rib 48 is formed, which extends "loh radially. It

030010/0811

9 and 10 are an embodiment analogous to FIGS. 1 to 4, the plates 46 being inserted into notches 34 of the corresponding support part by their rib 48 26 engage, while the shoulders 47 of these plates are in contact with the bearing surfaces 36, which on both sides such notches 34 are formed. At the point 45A pegs can be seen which are formed in one piece with the part 45 or are firmly connected and are riveted to the fingers 24.

In one embodiment (FIG. 11) it is an embodiment analogous to that described with reference to FIGS. 7 and 9: the plates 46 engage with their rib 48 in notches 40 of the corresponding support part 26, while their shoulders 47 as before are in contact with corresponding contact surfaces 36.

The foregoing also advantageously form the plates 46 Wearing parts for the woodruff spring 21 and are therefore advantageously able to protect them.

However, these designs are not absolutely necessary: the woodruff key can, if desired, directly axially rest on the support part 26 on both sides of the plate 46, which in this case only as their only Rib 48 is formed.

The above concerns the formation of the lugs which are used for the rotary connection of the disc spring 21 and the support part 26 are required, with a receiving part or recessed part or a nut piece on this support part is formed while a male part is formed on the disc spring.

In an embodiment variant (FIG. 12), a reverse arrangement can also be used: for each finger 24 the

030010/0811

- Ape -

Membrane 21 form the receiving devices which the support part 26 has, pegs or projections 50, wherein with each of these projections a fork 51 is in engagement, which is formed or fixed in one piece with this finger 24 connected with him.

In the illustrated embodiment, this fork 51 is formed by the plate 46, which carries the thickening, which is associated with the finger 24 in question, this plate comprising for this purpose a groove 52 which extends extends radially and by means of which the plate engages with the associated projection 50 is.

This fork 51 can, however, also be formed directly on the finger 24 with the aid of legs in the same way are punched out in these and are bent, for example, at an angle or at right angles.

Be that as it may, the flanks 53, which the projection 50 has at its ends pointing in the circumferential direction, form the small surfaces with which the lugs 54 cooperate in the rotary connection, which otherwise are branches the fork 51 form.

As before, these small surfaces 53 run parallel to the radial center plane of the finger 24.

In the embodiment variant shown in FIG. 13, which any of the embodiments described with reference to FIGS. 1 to 4 and 9 to 12 can be assigned are, the small surfaces, which thus have the support part 26, are each on two coplanar or support lines 60 ·, 60 "lying in a common plane reduced; these are support lines that run parallel to the axis of the assembly and are on beads 61 ', 61 " are formed, which protrude and carry the support part 26 and in pairs on the same radius

030010/0811

- Ait «μ

this part between two fingers 24 of the disc spring are arranged.

One does not escape the scope of the invention if one separates the facets or small areas in question in this way; it is seen the same for the embodiments shown to 8 in Figs. 5.

The present invention is not limited otherwise to the described and illustrated embodiments, but includes any embodiment and / or combination their various elements.

In addition, as already mentioned, the arrangements described can be used just as well on the driving pulley of a variable speed drive as on its driven pulley .

In particular, the receiving devices of the support, in which the lugs of the woodruff spring engage, do not necessarily penetrate this support part; as mentioned above, it may, in contrast, for example, also be blind-ending shots in the manner of a cup or the like..

030010/0811

Blank page

Claims (11)

Expectations 1. Pulley for variable speed gears, which has two coaxial flanges opposite to each other with a frusto-conical side surface, one of which is called a movable flange and is slidably mounted on a rotatable shaft while it is non-rotatably connected to it, and the other of which is more solid Flange is called and is not only rotatably connected to the shaft, but is also at least functionally axially connected to this, in cooperation with an elastic restoring device, which biases the movable flange in a direction towards the fixed flange, the elastic restoring device from an annular Part or a disc spring is formed, which on the one hand has a circumferential section which forms a disc spring and is in contact against the movable flange, 'and on the other hand has a central part which is divided into radial fingers which rest against a support part en, which is non-rotatably connected to the shaft in question and axially fastened thereon, with rotary connection lugs between the support part and the disc spring 030010/0811 are provided, which of the support part or woodruff are carried and are located in the circumferential direction on facets or small areas run parallel to the axis of the arrangement, characterized in that the lugs (33) from the Woodruff key (21) are carried, and that the small surfaces (e.g. 35) are firmly connected or fixed to the support part (26). are formed integrally with this. 2. Pulley for variable speed gear according to claim 1, characterized in that the small surfaces (e.g. 35) of the support part (26) parallel to a central, radial plane of the corresponding finger (24) of the woodruff spring (21) get lost. 3. Pulley according to claim 1, characterized in that that said small surfaces of the support part from the lateral flanks or side surfaces (35; 53) of receiving devices (34; 50) are formed which are included in this part. 4. Pulley according to claim 3, characterized in that the receiving devices have slots, notches or openings (34) or troughs into which engage the lugs (33) associated with them, and that the lugs are formed by the radial fingers (24) of the disc spring (21) or by parts (46) connected to these fingers. 5. Pulley according to claim 3, characterized in that the receiving devices are pins or projections (50) form, which forks (51) engage which are firmly or integrally connected to the disc spring (21), wherein the legs (54) of the forks form the noses. 6. Pulley according to claim 3, characterized in that the receiving devices (34) which the support part 030010/0811 2533801 for forming the lugs (33) of the disc spring (21), formed by a generally axial portion of the support part and that the tabs extend generally radially. 7. Pulley according to one of claims 3 to 6, characterized in that said small areas each are reduced to two support lines which run parallel to the axis of the arrangement, and that the support devices, which the support part (26) has, are formed by cylindrical projections (61 ', 61 "), which on the Support part (26) are carried, protrude axially and in pairs each assigned to the same radius of this support part are. 8. Pulley according to claim 3, characterized in that the receiving devices (34) which the support part (26) for the lugs (33) of the disc spring (21) on a generally radial portion of the support part are formed and that the tabs extend generally axially. 9. Pulley according to one of claims 1 to 8, characterized in that the diameter (D ₁ ) of the circumference, along which the disc spring (21) is supported axially on the supported (26), from the diameter (D ₂ ) of the ümfangs differs, along which the lugs (33) act for the rotary connection of the woodruff key and said support part. 10. Pulley according to one of claims 1 to 9, characterized in that the bearing surface (36) of the Support part (26), on which axially directly or indirectly a radial finger (24) of the woodruff key (21) rests, is a cylindrical section with generatrices which are perpendicular to the radial center plane of the finger. 030010/0811 29338Θ1 11. Pulley according to claim 10, characterized in that each radial finger (24) of the disc spring (21) is flat at least in the area in which it is intended for contact with the cylindrical portion (36) of the support part (26). 030010/0811